Electric contact-spring for trolley-harps.



.'A'. wL" COLE. ELECTRIC GONTAOT SPRING FOR TROLLEYHARPS.

AIoTIoN FILED SEPT. 2K8, 1905.

Patented 001;. 20, 17908,

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'UNITED sTATEs PATENT OFFICE.

ALBERT L.VCOLi"i. Ol? rifUB'LHNDALlil. ASS.\CHUSE'1`TS,k '.tSSlGNOR T() UNITED CO?PER FOUNDRY COMPANY, OI? IBOSTON, MASSACHUSETTS. A tlRPORATION tJF MASSACHU- SETTS.

ELECTRIC CONTACLSPRING Fon TROLLEY-uurs.

Patented oct. 2o, 190s.

' Appiicgaoniiiiea september 28.1905. semina. 2140,401.

To `all whom it may con-cern:

Be .it known that l; ALBERT InfCom, a

citij/ien 'ot' the lTinted States. residing at Xuburndale. in the county of Middlesex and State of Massachusetts. have invented an Iniproif'einent in llleciric Co1itaet-Springs for rli'olley-l-larps. of which the following description. in connection' with the accom! panying drawings, is afspecitication.- like let-- ters on the drawings representing like parts.

My invention relates particularly to overhead trolleys in which a trolley wheel is journaled in the arnis of a harp at the free end of a trolley pole through which the electric -currei'it is transmitted to the motor -of the car, niy invention residing in the provision of a 'contact spring for insuring con` stant. electrical contactbetween the Wheel andthe harp.

f`proi/ide a co-axially-arrangcd spring which serves the double purpose of holding the wheel properly centrally supported and alsoiof transmitting the electric current'. I n the preferred embodiment I provide'a lieti- 'cal spring. washer-like in shape (and to sonic extentl in function). preferably provided with I a central, cylindrical portion resting in a recess' for positioning the spring and also serving to press the saine constantly forward against the ends of the hubs of the v trolley wheel, said helical spring being reniovahly lieldat one end in the adjacent arin. thereby taiiiperating with the rotating wheclin giving more or less peripheral or circun'iferential resistance t'o tilting or swaying niet-ion of thc wheel on its axle (which is quite liable to take place when the bearing has worn loose).

In the ataronipanying drawings in 'which I. have illustrated a preferred embodiment of my invention. lt`igure 1 is a central vertical' sectional view thereof in the direction of the axis of the trolley wheelg'ltig. '.2 is a fragmentary view thereof showing the niaiu features of n'iy invention in side elevation;

Aand Fig. 3 is a detail in side elevation of the contact spring.

Mounted between the forked upper ends or arms 1, 2 of a harp 2i (which may be of any usual iii-'preferred form) is a usual trolley Wheel t mounted on an axle 5. these -parts being shown in more/'or less conventional"l'oiiu and various constructie'-.l .tetails thereof being onnttcd as not beingesl sential to a clear understanding of my invention. Y

Each arm of the harp is herein shown as provided with a recess G. and in this recess .spring 8 which constitutes thc main feature of .in v invention. This spring extends in a a slightly greater diameter thairthat of the hub l() of the trolley wheel, and its outer terminal 1l. is inade straight and bent slightly laterally to cntci' a pocket 12 formed there for in the arni of the harp head.

'The spring S is normally compressed or held undertension. tending to expand, thereby holding all the part's snugly and yet yieldingly.

ltwill thus be seen that l provide a spring which is at thi` saine time a washer and a contact' spring` serving both to transmit the current andto take all lateral ilu'uslisI of the trolley wheel and maintain ihc latter in proper central position and vertical alinenient. For instanccfi't the axial opening or bearing ta bushing usually being employed) becomes unduly worn so ihai the trolley tends to walible. it will be seen that the spring-washer at once counteracts this tendency by-otlering not merely a directinward pressure in the. dii'ectioii of thc axis. but also, because of thi` helical shape of the spring. offering a' resistance in the plane of rotation of the wheel. The contact` spring, however. cannot become uiiwouiid or unduly st 'ained because the outer end is held rigidly in the pocket` 12 and the. iiinci' cud is held in the recess ti. This construction. moreover, is exceedingly siinple 'and inexpensive to manufacture and at the saine t'iiiie otfcrs a iniiiiinuni wearing surface with absolutely sure contact'. '.lhc tlexible washer eti'ect and the. capacity for yielding. in all directions gives great eiidiii'aiice and wearing qualities. For these and other reasons l prefer. and herein elaiin` the combined washer and spring made 'out of wire wound as shown. but I do notv rel stirictuniyself in all cases thereto. as my vinvcntion may be applied in sheet metal struck up to the required shape.

ln practice. the opposite `springs` H are mounted in place with their ends l1 tii'nily inserted in the pockets 1'.) and their spiral oitiibular centers retained in thc recesses t'i. The trolley wheel t is then ii'isericd between is mounted thefspiral end 7 of the contactlint. disk-like or .spiral coil t). preferably to` of my y of the device which them and the axle put in place and secured, the spiral centers of the washer-springs automatically centering the latter for receivin said axle. As the trollev rotates, it is tightly pressed at theends of its hub by the opposite Washer-springs, the latter yielding both laterally and circumferentially to the varyingv movements of the wheel.

Besides the constructional features and advantages above pointed out, I wish to point out the additional distinguishing feature which resides in securing the Washerportion device to the harp as distinguished from directly securing the contact-spring portion. The helical part 'is the portion maintains unremittingr contact between the hub and the harp, and. therefore, constitutes the real contact spring, 'z'. e., the device which maintains perfectl and constant electrical circuit conditlons, while the flat or spiral part 9 constitutes the washer-portion of the device and' is the only portion of the device fastened to the har This is shown as inserted in a pocket, but 1t will be understood that it may be secured in other ways.

Having described my invention, what I- claim as new and desire Patent, is: j

l. A trolley harp, a trolley wheel journaled therein, and a combined washer' and contact spring mounted between the hub of the wheel and the harp and comprising a normally compressed disk -like Washer portion exharp 'for holding the spring tol secure by Letters pansible both- .radially and transversely of said Wheel, extending co-axially of said hub.

2. A trolley harp, a trolley Wheel journaled therein, and a combined washer andfcontact spring mounted co-axially between the harp 'Y and the hub o f the Wheel, saidcombin'ed washer and spring consisting of a on'e-piece Wire coiled into a radially extending fiat n Washer portion vprovided with means for directly securinfr 1t to the harp.

3. A trolley larp, a trolley wheel journaled .cumferential portion extending betWeenthe harp and Wheel and a terminal portion removably mounted in the harp.

5. A trolley harp, a trolley wheel journaled therein, and a spring bent in a continuous coil having its opposite ends retained by said the hu'b of the wheel.

In testimony whereof, I have signed my name to this specification, in the presence of two Isubscribing witnesses.

ALBERT L. COLE. Witnesses GEO. H. MAXWELL, M. A. JONES.

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